Homework expectations and detentions for not completing it

[SkankingWombat]

My yr4 child has had her set weekly homework increased from 4 to 5hrs a week, 2.5hrs minumum of which is screen-based and is often made up of 'busy work'. To be honest, we already found the 4hrs excessive and were finding it impossible to complete the work within those 4 hours, meaning we had to choose between never finishing a piece of work or spending many hours over and above what was expected. DD has ASD, ADHD and hypermobility, and getting her to sit and do this work is a struggle. Trying to fit it in around extracurricular activities, whilst also allowing time for her to play, relax, and pursue any other interests is already difficult.
To give a fuller picture, she does struggle with maths, largely because of her focus in lessons, so she has an hour's one-to-one tutoring for this in addition to her homework each week. She really enjoys going to the tutor, thankfully, so this doesn't cause upset and isn't viewed as 'work'. These sessions have had a very positive impact on her confidence and ability. She is also granted movement breaks throughout the school day and is removed from lessons for social skills interventions (this is relevant to what comes later).
The additional hour added is screen-based, which she finds harder to stay focussed on as well as the standard concerns about screen over-use, and is 'boring' in DD's words (ie no chance of convincing her to do it under the guise of a 'fun game'). It turns out the work on the app is actually well below her ability level (teacher confirmed this). I was happy to just quietly drop this aspect of the homework, and clearly so were a number of other parents because the school have introduced daily detentions for those who haven't completed the hour. DD is now missing part of her break, plus all the opportunity that brings to expel energy and build friendships, every day. It seems crazy to, on one hand, remove her from lessons to work on eg conflict resolution, then reduce the time she has to naturally put this into practise, requiring her to sit facing a screen with headphones on completing work that is below her level instead. I have both spoken to the teacher and emailed school, and it is like hitting my head against a brick wall. I have complained and stated I do not agree to any loss of playtime for this purpose to no avail. My personal preference would be to prioritise the work of greatest benefit and complete these pieces fully. School want it all done, but are prepared for us to do each element for the school-specified amount of time only and submit whatever is completed in this time. This still means doing much more work than she is able to comfortably manage, plus given the battle and time taken to get her started, focused and up to speed, they are likely to only have 20% of each task completed at best.

Is there anything I can do? Even without the SEN, the hours of set work is unreasonable, but with her additional needs it is causing real problems. She is completely demoralised, and we are having to manage homework meltdowns multiple times throughout the week. Dropping other elements of homework is not an option either, as school has also introduced a lunchtime 'homework club' for DCs who 'haven't been able to complete it at home'...

If you've already tried the class teacher, have you tried the SenCo? They might have a better understanding of the need to adapt expectations for your child, and the authority to tell the teacher that. The teacher is probably "following school policy" and trying to apply rules fairly to everyone, so it is the SEN which needs to override this.

Is it actually meant to take 5 hours!? That seems ridiculous for year 4! At that age ( admittedly from year 1 up) my DC got 10 minutes reading, spelling practice ( in theory 10 minutes but my ASD DD needs a fair bit of coaxing to do) daily and then a weekly worksheet that took about half an hour and they were told not to spend more than an hour on ( I assume the less able children don't finish). So in total 2-2.5 hours.
Senco is probably your best bet. My DD has it written into her plan she is not to miss break as that makes her behaviour worse. She will sometimes miss 10 minutes lunch for reflection but they make sure she always gets a chance to go outside.

5hrs, even 4hrs a week is completely excessive at this age. It is about the amount my secondary age child receives. Is this a state school? I agree with speaking to the SENCO.

Sadly, this is being driven by the headteacher, who is also the assistant SENCo ☹️
I'm in complete agreement that this is excessive for any 8/9yo. DC2 is in KS1, and she gets 30 mins plus reading, which feels totally appropriate. We happily support what she is given.

I might be wrong but I was under the impression that homework is not compulsory at primary schools. It might be different at a private or independent school but I think that is the case for state schools or it was when I taught in the classroom 5 years ago.
We also would only set weekly English and Maths homework and then half termly topic homework. All was optional and I'd only keep children in at break to complete it if the parents were struggling to get their child to do it at home and needed some support from school.
Sorry to hear about what your daughter is expected to do - it is way too much!

This is a state school (an academy though, which seem to be law unto themselves...).
Homework at Primary isn't compulsory, but 'just not doing it' means missing break, so we're over a barrel. School are also using the argument of "you agreed to follow our policies when you accepted the place", even though the new expectations are vastly different from what was the case 5 years ago.
I have also been told that this is mandatory because literacy (what the app is for) forms part of the national curriculum - well yes, but presumably the DofE expect this to be covered in lesson time, not on a screen at home with sanctions if not completed?